In additive or subtractive manufacturing processes, three-dimensional objects are produced taking a platform as the starting point. The platform can be, for example, arranged horizontally. The object is formed over the platform, and, in certain processes, also in a different position with respect to the platform, for example upside down below the platform, by successive layers being produced, the entirety of which layers constitutes the finished object. Examples of additive manufacturing processes are selective laser melting (SLM), selective laser sintering (SLS), electron beam melting (EBM), stereolithography (SL) and 3D printing (3DP). In many cases, overhanging layers which have to be supported arise during the manufacturing. To this end, support structures are formed, the support structures standing on the platform or on layers which have already been completed, and being connected to support points on the downwardly open surfaces of layers. If, during the manufacturing, the platform is located below an object, the support structures carry out a supporting function. In other situations, the support structures can be used for providing an attachment between object and platform or can carry out other carrying or supporting functions and are therefore quite generally also referred to as attachments. Such support structures can be formed, for example, from support struts or support walls which can be solid or hollow. This description proceeds from a horizontal platform located lowermost and an object arranged thereabove. However, all of the explanations also apply to a platform located uppermost or to a laterally or obliquely arranged platform, with respect to which an object is compiled from layers.
EP 2 198 405 B1 discloses support structures in the form of a mesh which supports individual support points of certain layers of an object. Said support structures consist of walls which are arranged in a diamond pattern. The support structures are erected without being oriented to locations of support points on the object. Instead, support points are connected to the closest junction of the support structure. This solution is disadvantageous insofar as it requires considerable outlay on material for the support structures. In addition, a considerable outlay is necessary in order to remove the support structures again.
DE 195 07 881 A1 reveals support structures which are likewise constructed from walls, the surfaces of which are provided with openings. Also disclosed are support structures consisting of struts which are interconnected and branch at increasing height above the object platform. Disadvantages of this approach again consist in that the exact position of support points on the object is not a priori taken into consideration. It is necessary, when this approach is used, to remove excess support struts of the support structure.
DE 601 22 219 T2 discloses support structures which have a triangular structure. Support struts, which are referred to as strands, are used as edges of the triangles. In order to optimize the support structures, certain distances between corner points of the triangles are used. However, the approach leaves room for improvement in respect of optimum stability and minimization of material.